The embodiment of the invention provides an insulation defect detection device and method for a transformer bushing. The insulation defect detection device comprises a quantum sensor, an electron paramagnetic resonance spectrometer and a processor, wherein the quantum sensor is arranged on the outer surface of the transformer bushing; the electron paramagnetic resonance spectrometer comprises a laser generator and a microwave transceiver, and is used for controlling the laser generator to emit laser to the quantum sensor to excite the quantum sensor, controlling the microwave transceiver to emit a microwave signal to the quantum sensor and receive a microwave signal fed back by the quantum sensor, and obtaining the distribution characteristics of the electric field and/or magnetic field intensity of the transformer bushing; the processor is used for judging whether or not the transformer bushing has a defect based on the distribution characteristics and determining the defect type in the condition that it is judged that the transformer bushing has a defect. The insulation defect detection device can conduct detection based on the distribution characteristics of the electric field and/or magnetic field of the transformer bushing and figure out the defect type of the transformer bushing.